Anglo-Siamese Treaty of 1909
Bangkok, Thailand
What happened
Representatives of Siam and Britain signed the treaty. Siam claimed overlordship of several Malay states to its south, while Britain ruled nearby Malaya. In Bangkok, Siam handed Kedah, Kelantan, Perlis and Terengganu to Britain, while Pattani and nearby areas stayed Thai. In return Britain gave up some special legal rights and lent money for a railway in southern Siam.
Why it matters
Why it matters: It set the modern border between Thailand and Malaysia. The four states later became part of Malaysia.
What came next
The four states became British protected states. They joined the Federation of Malaya, which became independent on 31 August 1957.
Did you know?
During World War II Thailand briefly took back the four states, but they returned to British control after the war.
Timeline
- 10 March 1909The treaty is signed in Bangkok.
- 9 July 1909Ratifications are exchanged in London.
- 1948Federation of Malaya is formed.
- 31 August 1957Malaya becomes independent.